Ventilated rib for shotguns



E. P. SIMMONS Filed March 24, 1948 INVENTOR, 27776:! 2 17277170 y 177/07/7effl VENTILATED RIB FOR SHOTGUNS Dec. 9, 1952 Patented Dec. 9, 1952 STATES PATENT 2 Claims.

This invention relates to new and useful improvements in ventilated ribs for shotguns, and has particular reference to sighting ribs.

Shotgun barrels, after extended periods of firing, become excessively hot, and heat waves rising from the barrel interfere with the line of sight, which normally extends longitudinally to and just above the gun barrel, so that objects sighted through said heat waves appear to have a shimmering movement very detrimental to accurate sighting. To overcome this difiiculty, ribs have'been provided to be positioned substantially parallel to and in spaced apart relation above the gun barrel, said rib serving to interrupt the heat waves rising from the barrel, and being maintained relatively cool by the free circulation of air between the barrel and the rib. The principal object of this invention is the provision of a ventilated sighting rib of the class described having certain improvements.

Another object is the provision of a plurality 'of longitudinally spaced, upwardly projecting support posts adapted to be rigidly fixed to a shotgun barrel, and an elongated rib supported at v cumferential grooves formed therein adjacent.

their upper ends, and an elongated rib adapted to be carried at the upper ends of said posts, said rib having longitudinal grooves formed in the lower surface thereof into which said posts project, the walls formed by the metal of said rib at each side of said groves being formed to project into the grooves of said posts, and means rigidly securing said rib to one of said posts.

Other objects are simplicity and economy of construction, efiiciency of operation, durability, and adaptability to be applied to various types of guns.

With these objects in view, as well as other objects which will appear in the course of the specification, reference will be had to the drawing, wherein:

Figure 1 is a side elevation of a shotgun with a ventilated rib embodying the present invention mounted thereon.

Fig. 2 is an enlarged fragmentary plan view of the gun and rib.

Fig. 3 is an enlarged fragmentary section taken on line III-III of Fig. 1.

Fig. 4 is a fragmentary section taken on line IV-IV of Fig. 3, with parts left in elevation.

Fig. 5 is a section taken on line VV of Fig. 4.

Fig. 6 is an enlarged fragmentary section taken on line VIVI of Fig. 1.

Fig. '7 is a fragmentary section taken on line VIIVII of Fig. 6.

Fig. 8 is a plan view of that portion of the rib shown in Fig. 7.

Like reference numerals apply to similar parts throughout the several views, and the numeral It! applies to a shotgun having a barrel 12, barrel assembly Hi, and breech assembly IS. A plurality of support posts I8 and a single anchor post 20 are carried in longitudinally spaced relation on the upper side of barrel I2, each of said posts having an enlarged foot 22 which is silver soldered or otherwise rigidly fixed to the barrel. Said posts project radially from. the barrel and are substantially equally spaced, anchor post 29 being disposed approximately midway in the series of support posts I8. The upper end portion 24 of each support post I8 is formed to present substantially an inverted frusto-conical shape, thereby forming a circumferential groove 25 in said post adjacent its upper end. The up per end of anchor post 20 is squared.

A rib 28 comprising an elongated metallic bar extending substantially the length of barrel [2 is adapted to be supported at the upper ends of post 18 and 28, being maintained in spaced apart relation from said barrel by said posts to permit free circulation of air therebetween. Said rib is rigidly fixed to anchor post 29 by any suitable means such as countersunk screw 30. A longitudinally elongated groove 32 is formed in the lower surface of rib 28 adjacent each support post l8, the frusto-conical end portion 24 of said post projecting upwardly into said groove and being adapted to permit free longitudinal sliding movement of the rib relative thereto. Grooves 32 are somewhat narrower than rib 28, thereby forming relatively thin walls 34 of metal at each side of said grooves. After the rib has been positioned over posts l8, portions of walls 34 are bent to project into the side portions of grooves 26 of said posts as indicated at 35, forming a sliding dovetail connection.

Thus rib 28 is firmly fixed to anchor post 20, and is secured at each post I8 against lateral or radial movement relative to barrel l2, but is permitted to move slidably over posts I8 longitudinally to the barrel. The rib, which is maintained relatively cool by the circulation of air thereunder and thus has a relatively small thermal expansion, is thereby prevented from interfering with the relatively great expansion of the hot gun barrel. Were the rib attached rigidly to the barrel along its entire length, or to all of post l8, this unequal expansion would tend to flex the barrel and rib in the manner of a bimetal strip, and would eventually loosen the connection between rib and barrel. The upper surface of rib 28 is knurled as shown in Fig. 8 to reduce reflection and glare therefrom.

A shorter rib 38 may be rigidly attached to the upper side of breech assembly I6 by suitable means such as countersunk screw 40, rib 38 being in substantially axial alignment "with rib '28 to provide a continuous line of sight to the end of the barrel. The adjacent ends of said ribs are spaced slightly apart as at 42. This gap permits free expansion of rib 28, and since it is 'disposed substantially at the line of division between barrelassembly I4 and breech assembly IE, it permits the disassembly of the barrel and breech assemblies in the usual-manner.

In shotguns having a recoil compensator 54 mounted at the end of the barrel, rib 28 terminates adjacent the rearward end thereof, being spaced apart therefrom by a gap 46 to permit free expansion of the rib. The upper surface of the rib is substantially coplanar with the upper edge .of the compensator. This is-a further advantage since the compensator then becomes scarcely ,noticeable to the gunner while aiming, it being largely obscured vfromview by therib. The appearance of a relatively large, bulbous compensator in distraetingjto many shotgun users.

In guns having compensators, the front sight 'bead "48 is .customarily mounted onthe compensator vas'shown, but could be mounted at the forward end of rib 2.8 on a gun without a compens'ator. The rear'sight bead 50' may be mounted on rib '28 intermediate its ends by any suitable --means. In the drawing, said bead is fixed to a tapered pin 52 adapted to be driven intoa matching tapered hole 54 formed in the rib.

It will be noted that rib 28 in the drawing is inclined relative to barrel 12, being closer to the axis .of the barrel at the muzzle than at the breech. Since the line of aim is determined by beads 48 and-53, this inclination is not important, and is dictated largely by the contours of the .particulargun to Whichthe rib is'applied. How- .eveinif for any reason it should be desirable to dispose the rib parallel to the barrel. it is obvious that it could be accomplished simply by varying theilelig'ths of support posts l8 and anchor post 20. This and many other minor variations of structure could be made without departing from f the :spirit .of the invention.

What I claim is:

1. In'combination with a shotgun having a barrel, an anchor post and a plurality of support posts rigidly fixed independently to said barrel in longitudinally spaced relation and extending radially outwardly therefrom, each of said support posts being circumferentially grooved adjacent its outer end to form an outwardly divergent tapered end portion, and an elongated metallic rib disposed substantially parallel with said barrel and adapted to be carried at the outer ends of said anchor and support posts in spaced relation to said barrel, said rib being fixed rigidly to said anchor post and having a longitudinally elongated rectangular groove formed in the lower surface thereof adjacent each of said support posts to receive the tapered end portion of said post, said groove being of such width as to leave a relatively thin wall of metal at each side thereof, and the central portions of said walls being formed to project into the circumferential roove of said support post.

2. In combination with a shotgun having a barrel, an anchor post and aplurality ofsupport posts rigidly fixed independently to said barrel in longitudinally spaced relation and extending radially outwardly therefrom in an axial-planeof said barrel, said anchor post being disposed approximately centrally in said series of posts and each-of said support posts being-circumferentially grooved adjacent its outer end to form an outwardly divergent end portion, and an-elongated metallic rib having its upper surface knurled disof such width as to leave relatively thin parallel walls of metal at each side thereof, and the central portions of said walls being formed to project into the circumferential groove of said support post. 1

ERNEST P. SIMMONS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number .Name Date 805,588 Stannard et a1. Nov. 28, 1905 1,137,477 Godshalk Apr. 27, 1915 1,323,149 Blizard Nov. 25, 1919 1,323,151 Burton Nov. 25, 1919 1,705,423 Smith Mar. 12, 1.929 1,718,458 Hager et al June 25', 19.29 2,431,991

Crowe Dec. 2, 194-7 

